Distillate and raffinate



United States Patent 3,206,403 MINERAL OIL CONCENTRAT-ES CONTAG NON-ASH-FORMRNG OIL ADDITIVES Bobby W. Malone, East Norwalk, Conn., and Julian G. Ryan, Wood River, 'Ill., assignors to Shell Oil Company, New York, N .Y., a corporation of Delaware No Drawing. Filed July 22, 1964, Ser. No. 384,534 7 Claims. (Cl. 252-493) This application is a continuation-in-part of our copending applications Serial No. 112,752, filed May 26, 1961, Serial No. 863,098, filed December 31, 1959, and Serial No. 776,419, filed November 26, 1958, all of which are now abandoned.

The present invnetion relates to mineral oil concentrates of certain non-ash-forming additive mixtures, which concentrates are compatible with and stably dispersible in any liquid mineral lubricating oil which may be neat or compounded.

It is known that certain oil-soluble non-ash-forming nitrogen-containing polymeric detergents in which the nitrogen-containing groups may be amido groups such as vinyl pyrrolidones, in conjunction with a p,p'-methylene bisphenol where the Rs are alkyl groups, preferably tertiary alkyl groups, when added in small amounts to lubricating oils impart to the oil a high degree of stability and excellent detergency. However, it has been observed that the type of oil to which these additives are added is critical if separation of the additives from the oil is to be prevented particularly when oils containing the additive mixture are stored in concentrated form and later blended with conventional lubricating stocks such as commercial mineral lubricating oils, which be neat or compounded with conventional oil additives such as sulfonates, organic phosphites, phosphates, phosphonates or their thio-derivatives, phenates, thiocarbamates, aromatic or aliphatic amines, etc., to give a finished lubricant.

A principal object of the invention is to provide a min eral oil concentrate containing certain polymeric nitrogencontaining detergents and p,p'-metl1ylene bisphenols which are stably dispersible in any lubricating oil. Another ob ject of the invention is to provide a mineral oil concentrate containing said two additives which concentrate is dispersible in conventional mineral lubricating oils and are stably suspended or dispersed tlrerien both during storage and use. to provide a mineral oil concentrate containing said two additives which when added to conventional mineral lubricating oil would meet and pass revised MIL-L-6082B and MIL-L-22851 specifications. Another object of the present invention is to provide a mineral oil concentrate containing substantial amounts of each of said two additives which when added to lubricating oils would result in excellent aircraft and automotive lubricants. Other objects will be apparent from the following description.

Still another object of the invention is It has now been discovered that the additive combina- 3,206,403 Patented Sept. 14, 1965 15%, preferably 20% to about 60% or higher preferably 40% of the polymeric detergent and from about 3%, preferably 5% to about 20% or higher, preferably about 15% by weight of. the p,p'-methylene bisphenol, in a highly refined East Texas raffinate mineral oil fraction containing from 20m 30 carbon atoms, essentially free of sulfur compounds and tri-, tetra-, penta-, hexaaromatics but a substantial portion of which, namely 10% to 30% are monoand diaromatics and the balance being saturates which includes alkanes, condensed and noncondensed cycloalkanes, said oil having a molecular weight range of from 280 to 500 and a VI of from to 100. It is preferred that the weight ratio of the polymer to the bisphenol in the concentrate be from 15:1 to about 5:1, preferably from about 10:1 to about 8:1, respectively. East Texas base mineral oil concentrates of this type can be added to any type of mineral oil in any desired concentration without worry of separation, compatibility, interaction or other undesirable side effects both during storage or use.

The detergent copolymers useful in forming concentrates of the present invention include copolymers of vinyl pyrrolidone and polymerizable acrylates and methylacrylates such as N-vinyl pyrrolidone and C alkyl acrylate e.g. lauryl methylacrylate or similar copolymers as described in Belgian Patent 550,422 and British Patent 808,- 664, and mixtures thereof. Acrylate-vinyl pyrrolidone copolymers are sold by Rohm and Haas under the desig nations Acryloid 315X or 917 or 966 and are copolymers of N-vinyl pyrrolidone and lauryl methacrylate of varying molecular weight of from about 100,000 to about 650,000.

The long chain acrylate esters used in the preparation of the copolymers include the esters of acrylic acids and long chain aliphatic alcohols. Examples of the acrylic acids include acrylic acid and the alpha-substituted acrylic acids such as methtacrylic acid, ethacrylic acid, alphaphenyl acrylic acid, alpha-cyclohexyl acrylic acid and chloroacrylic acid. The long-chain aliphatic alcohols used in the esterification of these acids may be exemplified by decyl, lauryl, cetyl, stearyl, eicosanyl, nonadecanyl alcohols and the like and mixtures thereof. Particularly preferred esters to be used are the acrylic acid and meth acrylic acid esters of aliphatic monohydric alcohols, and especially alkyl alcohols, containing from 14 to 20 carbon atoms.

Specific examples of these long chain acrylic acid esters include, among others, decyl acrylate, lauryl acrylate, stearyl acrylate, decyl methacrylate, lauryl methacrylate, cetyl methacrylate stearyl methacrylate, eicosanyl acrylate, docosanyl acrylate, and the like, and mixtures thereof.

As noted, a mixture of one and preferably two or more of these long chain acrylate esters can be used in making the copolymers. Illustrative examples of these ester mixtures include, among others, dodecyl methacrylate/tetradecyl methacrylate, tetradecyl acrylate/octadecyl methacrylate, decyl methacrylate/octadecyl methacrylate; tetradecyl methacrylate/hexadecyl methacrylate; tetradecyl methacrylate/octadecyl methacrylate; dodecyl methacrylate/eicosanyl acrylate, and the like.

In the mixtures, it is highly desirable to have a substantial difference in the number of carbon atoms of the alcohol portion. Particularly superior results are obtained when one of the acrylate esters is a C to C acrylate ester and the other is a C to C acrylate ester.

In the mixtures, the different long chain acrylate esters are employed in mol ratios from 1:4 to 4:1. The snperior copolymers are obtained when the higher ester, e.g., those having from to carbon atoms in the alcohol portion, and the lower esters, e.g., those having from 10 to 14 carbon atoms in the alcohol portion are combined in a mol ratio varying from 1:1 to 1:3.

Copolymers of the present invention which have the superior properties above are those having molecular weights between 50,000 and 2,500,000 as determined by the light scattering technique described in Chem. Rev., vol. 40, page 319 (1948). Preferably, the molecular Weights range from about 75,000 to 1,000,000 and more preferably from 100,000 to 650,000.

The following examples illustrate the preparation of suitable polymers for use in compositions in accordance with the invention. Unless otherwise specified, parts disclosed in the examples are parts by weight.

In the examples, the molecular weights were determined by light scattering method and the ratio of vinyl pyrrolidones to alkyl ester was determined by analysis for nitrogen.

EXAMPLE I A mixture of about 2 mols of lauryl methacrylate, 1 mol of N-vinyl pyrrolidone and 0.5% by weight of benzoyl peroxide was reacted in a suitable reaction vessel for a period of about 10 hours at about 65 C. The polymer was then dispersed in benzene and thereafter precipitated with a mixture of acetone and methanol. A copolymer of lauryl methacrylate/N-vinyl pyrrolidone having a nitrogen content of 2.20% by weight and a molecular weight in excess of 250,000 was recovered. The polymer contained the monomer units essentially in the ratio as provided in the mixture; it had an alkane chain of about 2400 carbon atoms carrying about 800 lauryloxyformyl groups and about 400 butylolactam groups.

EXAMPLE II A copolymer of lauryl methacrylate and N-vinyl pyrrolidone was prepared by the method of Example I with the same monomer ratio but in which 0.75% by weight of alpha,alpha-azodiisobutyronitrile was used as the catalyst. The molecular weight of the polymer was around 225,000.

EXAMPLE III A terpolymer of stearyl methacrylate/lauryl methacrylate/N-vinyl pyrrolidone in the mol ratio of 2.8/ 5.6/ 1, respectively, was prepared essentially by the method of Example I using 0.2% alpha,alpha-azodiisobutyronitrile as catalyst and the reaction time was 48 hours. The polymeric product was oil-soluble and had an average molecular Weight over 1 10 as determined by the light scattering technique.

Other representative copolymers useful in compositions of this invention include those identified below in which the monomeric units are present in the mol ratios of 1:1, 1:2, 1:4, 1:6, of the monomer, one to the other, and preferably of N-vinyl pyrrolidone to ester, respectively, said copolymers having a molecular weight in excess of 50,000: N-vinyl pyrrolidone/octyl methacrylate, N-vinyl-3-methyl pyrrolidone/cetyl methacrylate, N- vinyl pyrrolidone/stearyl methacrylate, N-vinyl pyrrolidone/stearyl acrylate, N-vinyl-3,3-dimethyl pyrrolidone/lauryl methacrylate, N-vinyl pyrrolidone/stearyl methacrylate/cetyl methacrylate, N-vinyl-3-methyl pyrrolidone-stearyl methacrylate/lauryl methacryla-te, and

mixtures thereof.

The methylene bisphenol represented by the above structural Formula A can be prepared by any suitable means such as by reacting a di-tertiary alkyl phenol with formaldehyde in the presence of an organic solvent such as heptane and an acidic catalyst such as sulfuric acid. Another method is to react the di-tertiary alkyl phenol with formaldehyde in the presence of an acid catalyst in an aqueous medium. The general method of preparing these compounds is well known in the art and does not form a part of the present invention. Compounds of this type include 4,4-methylene bis(2,6-ditertiarybutyl phenol), 4,4'-methylene bis(2,3-ditertiarybutyl phenol), 4,4'-methylene bis(2,5-ditertiarybutyl phenol), 4,4- methylene bis(3,5-ditertiarybutyl phenol), 4,4-methylene bis(2,6-ditertiaryoctyl phenol), 4,4'-methylene bis(2- tertiarybutyl, 6-tertiaryoctyl phenol), and mixtures thereof.

The East Texas rafiinate mineral oil base used to form the concentrate containing the two essential additives described above not only function as a carrier for the additives in the concentrate, but as a solubilizer to the additives when from about 10% to about of the concentrate is added to any mineral lubricating oil to form stable finished lubricating oil compositions. The East Texas refinate fraction used in forming the concentrate is a highly refined East Texas raffinate fraction containing from about 20 to about 30 carbon atoms and is essentially free of sulfur, nitrogen and oxygen constituents as well as higher polyaromatics such as the tri-, tetra-, penta-aromatics, e.g., the phenanthrenes, anthracenes, dibenzothiophenes, chrysenes, pyrenes, etc., and resins, but which is rich in monoand diaromatics (1030%) and saturates which include alkanes, non-condensed and condensed cycloalkanes totaling 70-90% of the hydrocarbon mixture. The VI of such ratfinate fractions ranges from 75 to and the molecular weight varies from about 280 to about 500. East Texas raffinate fractions used in formin the concentrate of the present invention may be obtained by solvent (phenol or furfural) extraction of suitable East Texas distillates having a viscosity range of to 400 SUS at 100 F. A typical East Texas distillate (250 SUS 100 F.) from which, by phenol extraction, suitable rafiinate fractions can be obtained ranging in VI from 75 to 93 on analysis contained the following hydrocarbon types.

Table I COMPONENTS OF 250 EAST TEXAS (ET) DISTILLATE Components, percent wt.: Distillate n-Alkanes 13.1

Isoalkanes 10.8 Noncondensed cycloalkanes 26.7 Condensed cycloalkanes 16.9

Total saturates 67.5

Monoaromatics 13.7

Diaromatics 5.8

Triaromatics 4.2

Tetraaromatics 2.1

Pentaaromatics 1.5

Hexaaromatics 0.5 Total sulfur compounds 4.7

Total 100.0 Sulfur analysis, percent wt.:

Thiophenes Benzo- 1.6

Triaromatics 0.6

Tetraaromatics 0.3

Pentaaromatics Other sulfur compounds 2.2

Total 4.7

The rafiinate fraction obtained from the above distillate by phenol extraction followed by methyl ethyl ketonetoluene treatment contains the following components and this East Texas (ET) is an excellent carrier for the additives of the present invention whereas raffinates obtained from other sources, e.g., West Texas-Ellenberger (WTE) or Oklahoma fraction (0C) are unsuited and their compounds are shown in Tables III and IV.

Table II COMPONENTS OF ET 250 RAFFINATE Components, percent wt.: Rafiinate n-Alkanes 17.3 Isoalkanes 15.8 Noncondensed cycloalkanes 34.0 Condensed cycloalkanes 18.4

Total saturates 85.5 Monoaromatics 10.4 Diaromatics 2.7 Triaromatics 0.8

Tetraaromati-cs 0.2

Pentaaromatics Hexaaromatics Total sulfur compounds 0.4

Total 100.0 Sulfur analysis, percent wt.:

Thiophenes- V Benzo- 0.2 Triaromatics 0.1 Tetraaromatics 0.1

Pentaarornatics Other sulfur compounds Total 0.4

Table III COMPONENTS OF WEST TEXAS-ELLENBERGER (WTE) 250 DISTILLATE AND RAFFINATE Distillate Rafiinate Components, Percent wt.:

n-Alkmms Isoalkanes Noncondensed Cycloalkaues Condensed Cycloalkaues Total Saturates Monoarornatics Diaromatics.-- Triaromatic Tetraaromatics. Pentaaromatics. Hexaaromatics Total Sulfur Compounds Total Sulfur Analysis, Percent wt.:

Thiopheues Benzo- Triaromatics Tetraaromatics Pentaaromatics Other Sulfur Compounds Total Table IV COMPONENTS OF OKLAHOMA (DC) 250 DISTILLATE AND RAFFINATE Distillate Raflinate Components, Percent wt.:

n-Alkanes Iso alkanes Noncondensed Cycloalkan Condensed Cycloalkanes Total saturates- Monoaromatics Diaromatics Triaromatics Tetraaromatics Pentaaromatics..- Hexaaromatics Total Sulfur Compounds Total Sulfur Analysis, Percent wt.:

Thiop enes:

Benzo- Triaromatics..- Tetraaromatics Pentaaromatics Other Sulfur Compounds Total r snow 1'' 99999 a romance:

The East Texas rafiinate (Table II) shown above is excellent for forming the concentrate of the present invention. However, oil fractions in the same viscosity range as the East Texas rafiinate such as obtained from West Texas-Ellenberger (WTE) or Poso Coalinga or Oklahoma crudes shown in Tables IV and V are unsuited for forming the concentrates of the present invention since such concentrates when blended with conventional lubricating oils such as SAE 5W to mineral lubricating oils or aviation oils of the so-called 1100 or 1065 grade aircraft oils or the 80 or viscosity grade aviation oils present a compatibility problem particularly when such oils contain conventional antioxidants, e.g., alkyl phenols, aromatic amines, or metallic detergents, e,g., oil-soluble metal sulfonates, phenates, wear inhibitors, e.g., metal organic phosphates, thiocarbamates, etc.

A preferred embodiment of the. present invention is to blend 1020% of concentrate with an East Texas lubricating oil in the viscosity range (SAE 5W90) so as to form the final or finished lubricant and if desired add to the concentrate or the finished product a small amount (0.013%, preferably 0.11%) of a partial or full ester of an organic phosphorus compound. Phosphorus compounds of this type include alkyl, cycloalkyl, alkaryl, aralkyl, and aryl phosphites, phosphates, phosphonates, and their thio-derivatives, such as C alkyl phosphites, e.g., diand tributyl, octyl, lauryl, stearyl, cyclohexyl, benzyl, cresyl, phenyl phosphites or phosphates, as well as their thio-derivatives; P S -terpene re action product, P S -pine oil reaction product; dibutyl methane-phosphonate, dibutyl trichloromethane phosphonate, dibutyl monochloromethane phosphonate, dibutyl chlorobenzene phosphonate, and the like. The esters of pentavalent phosphorus acids such as diphenyl, dicresyl, triphenyl, tricresyl, trilauryl and tristearyl ortho phosphates, P S -terpene reaction products and mixtures thereof are preferred.

Concentrates illustrating the present invention are shown below.

Table V A Concentrate, percent wt 10 Percent East Texas 250ll00 F. SUS rafiinate 1 67 Percent Example I copolymer 30 Percent 4,4-methylene bis(2,6-ditertbutylphen 3 P ROPE RIIES Vis., 880 at:

1 2700 210 F- 346 Four point, F 20 Gravity, APT 28. 2 Storage Stability, Days 50 PROPERTIES OF CONCENTRATES IN AIRCRAFT OIL 1100 MIL Spec 6082B Vis. SSU at- 100 F 1298 210 F Viscosity index 111 Ash, percent wt 0. 0001 Neutralization No 05 Neutrality Neut Precipitation N o 0 Copper corrosion 1A Sulfur, percent wt 0.13 Saponification No 1. 2 Flash, COC, F 495 Fire, COC, F- 560 Cloud point, F 40 Four point, F. 10 F max 10 Diluted pour point, F B455 Carbon residue, percent wt 1.2 max 0. 06 Gravity, API. 27. 8 Storage stability, days 50 1 Note Table II. Viscosity specification set by Navy for 1100-grade aircraft OllS containing mineral oil concentrate.

The above concentrate A made with different stocks such as Oklahoma or West Texas in the same viscosity range or blended with a 1100 aircraft oil would on storage separate in 10-15 days.

aeocnes Examples of other concentrates of the present invention are shown in Table VI:

acrylate and from to by weight of 4,4'-methylene bis(2,6-dialkylphenol) and the balance being an East tially of a mixture of from to 40% by weight of a copolymer of vinyl pyrrolidone and a C1248 alkyl meth- T able VI B 0 D E F G Concentrate, percent wt.

Example I, percent G0 a 30. Example II, percent as 30,. 40 Example III, percent 30 50 4,4-methylene bis(2,0-

ditertbutylhpenol) percent 6 '1 3. i 3 4,4anethylene bis(2,6-

oetylphenol) perceut Tricresyl phosph 1.5 Dicresyl phosphate 1 Dimethy1silieone 50 p.p.m 50p.p.m p.p.m. 25 p.p.m 50p.p,rn. ET 250/100, percent. Balc Bale Bale Bale Bale. ET 350/100, percent. Balc (50/50mixtureof ET250 and JET-550 at 100F).

Concentrates B, C and D diluted with 90% of 1100 Texas mineral lubricating oil rafiinate fraction consisting aircraft oil were storage stable for over 50 days; Conessentially of 10 to by weight of monoand diarocentrates E and F diluted with 80% West Texas-Ellenmatics and 9070% by weight of saturates. berger oil (250/ 100 F.) were stable for over days 25 4. A mineral oil additive concentrate consisting essenand Concentrate G diluted with Oklahoma 250/100 tially of a mixture of from 20 to 40% by Weight of a F. mineral lubricating oil was stable for over 50 days copolymer of vinyl pyrrolidone and lauryl methacrylate and these compositions passed all requirements of MIL- and from 5 to 15% by weight of 4,4-methylene bis(2,6- L-6085B and MlLL-22851 specification. On the other ditertbutyl phenol) and the balance being an East Texas hand, when in these concentrates the East Texas rafiinate 30 mineral lubricating oil raflinate fraction consisting essenwas substituted with dififerent base stocks such as a Posotially of 10 to 30% by weight of monoand diaromatics Coalinga or WTE lube oil stock and these concentrates and 90-70% by Weight of saturates. were diluted with 1100 aircraft oil, or WTE, or Okla- 5. A mineral oil additive concentrate consisting essenhoma lube oil stocks, as indicated in Table VI, the tially of a mixture of about 30% by Weight of a copolystorage stability was reduced 50 to and these 35 mm" of vinyl pyrrolidone and lauryl methacrylate and compositions failed to pass the above specification requireabout 3% by Weight of 4,4'-methylene bis(2,6-ditertbutyl t phenol) and the balance being an East Texas mineral Concentrates of th present inventio may b us d a lubricating oil rafiinate fraction consisting essentially of lubricants per se. When diluted with suitable mineral 10 t0 y Weight of m n d dia matics and oils as described, the finished products possess improved 4O 70% y Weight of saturatesstorage, detergency and oxidation stability. 6. A mineral oil additive concentrate consisting essen- We claim as our invention: tially Of a mixture Of about 60% by weight Of a copoly- 1. A mineral oil additive concentrate consisting essenmef of Vinyl pyrr and ryl meth crylate and tially of a mixture of from about 15% to about 60% by about 6% y Wbigbt 0f 4,4"methy1bne bi$(2,6-diter1b11tl1 weight of a copolymer of vinyl pyrrolidone and a C 5 phenol) and the balance being an East Texas mineral alkyl methacrylate and from 3% to 20% by Weight f lubricating oil raffinate fraction consisting essentially of 4,4'-methylene bis(2,6-dialkylphen0l) and the balance 10 t0 y Weight of mOIlO- and diaromatics n being an East Texas mineral lubricating oil rafiinate 7 y Weight of sfltlll'atesfraction consisting essentially of from 10% to 30% by T n n at of 01mm 4 onralning from 1 to weight of monoand diaromatics and 9070% by Weight 50 5% by Weight of trrcresyl phosphate. of saturatejs' References Cited by the Examiner 2. A mineral Oli additive concentrate conslstmg essentially of a mixture of from about 15% to about 60% by UNITED STATES PATENTS weight of a copolymer of vinyl pyrrolidone and lauryl 2,498,628 2/50 Cyphers et al. 25249.8 X methacrylate and from about 3% to about 20% by Weight 55 2,807,653 9/57 Filbey et al. of 4,4-'-methylene bis(2,6-ditertbutyl phenol) and the bal- 2,886,523 5/59 Claridge et al. 20818 X ance being an East Texas mineral lubricating oil rafiinate 3,030,303 4/ 62 Ryan 25251.5 X fraction consisting essentially of from 10% to 30% by weight of monoand diaromatics and 90-70% by weight FOREIGN PATENTS of saturates 808,665 2/59 Great Britain.

3. A mineral oil additive concentrate consisting essen- 351 5 3 10 0 Great i i DANIEL E. WYMAN, Primary Examiner. 

4. A MINERAL OIL ADDITIVE CONCENTRATE CONSISTING ESSENTIALLY OF A MIXTURE OF FROM 20 TO 40% BY WEIGHT OF A COPOLYMER OF VINYL PYRRLIDONE AND LAURYL METHACRYLATE AND FROM 5 TO 15% BY WEIGHT OF 4,4''-METHYLENE BIS(2,6DITERTBUTYL PHENOL) AND THE BALANCE BEING AN EAST TEXAS MINERAL LUBRICATING OIL RAFFINATE FRACTION CONSISTING ESSENTIALLY OF 10 TO 30% BY WEIGHT OF MONO- AND DIAROMATICS AND 90-70% BY WEIGHT OF SATURATES.
 7. THE CONCENTRATE OF CLAIM 4 CONTAINING FROM 1 TO 5% BY WEIGHT OF TRICRESYL PHOSPHATE. 